isp_handle_index
uint32_t isp_handle_index(ispsoftc_t *, uint32_t);
hidx = isp_handle_index(isp, rq->req_handle);
hidx = isp_handle_index(isp, handle);
hidx = isp_handle_index(isp, rq->req_handle);
hidx = isp_handle_index(isp, handle);